Field of the Invention
This invention relates generally to roll-fed copying machines and more particularly to the apparatus and control circuitry for dispensing cut lengths from a roll of copy sheet material in accordance with varying size originals and wherein switches responsive to the presence and absence of an original are used in the control circuitry.
While roll-fed copy machines are known which use one or more switches that are operated in accordance with the presence or absence of original sheets fed into the machine and/or the presence or absence of copy paper for controlling the movement of copy sheet material from a supply and the cutting of the material to length corresponding to the length of the originals, such prior arrangements are complex and relatively expensive. For example, the prior arrangements may require the use of special circuit components to provide pulsed operation of solenoids or the use of expensive continuous duty solenoids. In addition, many of the prior art arrangements require special control features or mechanisms to avoid jamming of copy paper at the cutter when the cutter is operated. While circuit complexity of the prior art was reduced by an arrangement using two switches disclosed in U.S. Pat. application Ser. No. 945,407, filed Sept. 25, 1978, now U.S. Pat. No. 4,193,330, careful adjustment of the switch positions is required which is time consuming and complicates maintenance when either of the switches requires replacement.